if (i == 10) {
        new Thread(() -> latch.countDown()).start();
      }

      future.addListener(listenerLatch::countDown, exec);
    }

    assertSame(Boolean.TRUE, future.get());
    // Wait for the listener latch to complete.
    listenerLatch.await(500, MILLISECONDS);

    exec.shutdown();
    exec.awaitTermination(500, MILLISECONDS);
  }

      threadUnexpectedException(t);
    }
  }

  /**
   * Just like assertSame(x, y), but additionally recording (using threadRecordFailure) any
   * AssertionFailedError thrown, so that the current testcase will fail.
   */
  public void threadAssertSame(Object x, Object y) {
    try {
      assertSame(x, y);
    } catch (AssertionFailedError t) {
      threadRecordFailure(t);
      throw t;
    }

    Optional<String> optionalName = Optional.fromNullable("bob");
    assertEquals("bob", optionalName.get());
  }

  public void testFromNullable_null() {
    // not promised by spec, but easier to test
    assertSame(Optional.absent(), Optional.fromNullable(null));
  }

  public void testIsPresent_no() {
    assertFalse(Optional.absent().isPresent());
  }

    List<? extends Future<?>> unused = executor.invokeAll(tasks);
  }

  public void testListeningDecorator() throws Exception {
    ListeningExecutorService service = listeningDecorator(newDirectExecutorService());
    assertSame(service, listeningDecorator(service));
    List<Callable<String>> callables = ImmutableList.of(Callables.returning("x"));
    List<Future<String>> results;

    results = service.invokeAll(callables);

    Iterator<String> mod = Lists.newArrayList("a", "b", "c").iterator();
    UnmodifiableIterator<String> unmod = Iterators.unmodifiableIterator(mod);
    assertNotSame(mod, unmod);
    assertSame(unmod, Iterators.unmodifiableIterator(unmod));
    assertSame(unmod, Iterators.unmodifiableIterator((Iterator<String>) unmod));
  }

  @SuppressWarnings("deprecation")
  public void testPeekingIteratorShortCircuit() {

    Iterator<String> mod = Lists.newArrayList("a", "b", "c").iterator();
    UnmodifiableIterator<String> unmod = Iterators.unmodifiableIterator(mod);
    assertNotSame(mod, unmod);
    assertSame(unmod, Iterators.unmodifiableIterator(unmod));
    assertSame(unmod, Iterators.unmodifiableIterator((Iterator<String>) unmod));
  }

  @SuppressWarnings("deprecation")
  public void testPeekingIteratorShortCircuit() {

      threadUnexpectedException(t);
    }
  }

  /**
   * Just like assertSame(x, y), but additionally recording (using threadRecordFailure) any
   * AssertionFailedError thrown, so that the current testcase will fail.
   */
  public void threadAssertSame(Object x, Object y) {
    try {
      assertSame(x, y);
    } catch (AssertionFailedError t) {
      threadRecordFailure(t);
      throw t;
    }

    builder.add("a");
    assertEquals(1, builder.size);
    builder.add("b", "c", "d");
    assertEquals(4, builder.size);
    Object[] table = builder.hashTable;
    assertNotNull(table);
    assertSame(table, ((RegularImmutableSet<String>) builder.build()).table);
  }

  @GwtIncompatible("Builder impl")
  public void testPresizedBuilderForceCopy() {
    for (int expectedSize = 1; expectedSize < 4; expectedSize++) {

    Object key = new Object();
    Object value = new Object();
    LoadingCache<Object, Object> cache =
        builder.build(CacheLoader.from(Suppliers.ofInstance(value)));
    assertSame(value, cache.getUnchecked(key));
    assertEquals(0, cache.size());
    assertFalse(cache.asMap().containsKey(key));
  }

  public void testCacheBuilderFrom_string() {
    CacheBuilder<?, ?> fromString =

    Iterable<String> iterable2 = Iterables.unmodifiableIterable(iterable);
    assertSame(iterable, iterable2);
    ImmutableList<String> immutableList = ImmutableList.of("a", "b", "c");
    assertSame(immutableList, Iterables.unmodifiableIterable(immutableList));
    assertSame(immutableList, Iterables.unmodifiableIterable((List<String>) immutableList));
  }

  public void testFrequency_multiset() {